How severe is CVE-2021-24376?

CVE-2021-24376 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-24376 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24376?

CVE-2021-24376 affects Autoptimize. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-24376?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-24376 published?

CVE-2021-24376 was published on 2021-06-21 and last updated on 2026-06-17.

CVE-2021-24376

CVE-2021-24376 is a critical-severity vulnerability in Autoptimize with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-434.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Autoptimize
Published: 2021-06-21
Last modified: 2026-06-17

Description

The Autoptimize WordPress plugin before 2.7.8 attempts to delete malicious files (such as .php) form the uploaded archive via the "Import Settings" feature, after its extraction. However, the extracted folders are not checked and it is possible to upload a zip which contained a directory with PHP file in it and then it is not removed from the disk. It is a bypass of CVE-2020-24948 which allows sending a PHP file via the "Import Settings" functionality to achieve Remote Code Execution.

Frequently asked questions

What is CVE-2021-24376?: The Autoptimize WordPress plugin before 2.7.8 attempts to delete malicious files (such as .php) form the uploaded archive via the "Import Settings" feature, after its extraction. However, the extracted folders are not checked and it is possible to upload a zip which contained a directory with PHP file in it and then it is not removed from the disk. It is a bypass of CVE-2020-24948 which allows sending a PHP file via the "Import Settings" functionality to achieve Remote Code Execution.
How severe is CVE-2021-24376?: CVE-2021-24376 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-24376 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24376?: CVE-2021-24376 affects Autoptimize. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-24376?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-24376 published?: CVE-2021-24376 was published on 2021-06-21 and last updated on 2026-06-17.

References

https://wpscan.com/vulnerability/93edcc23-894a-46c2-84d2-407dcb64ba1e

Affected products (1)

cpe:2.3:a:autoptimize:autoptimize:*:*:*:*:*:wordpress:*:*

More vulnerabilities in Autoptimize

CVE-2021-24377 — High (CVSS 8.1): The Autoptimize WordPress plugin before 2.7.8 attempts to remove potential malicious files from the extracted archive…
CVE-2020-24948 — High (CVSS 7.2): The ao_ccss_import AJAX call in Autoptimize Wordpress Plugin 2.7.6 does not ensure that the file provided is a…
CVE-2023-2113 — Medium (CVSS 4.8): The Autoptimize WordPress plugin before 3.1.7 does not sanitise and escape the settings imported from a previous…
CVE-2022-2635 — Medium (CVSS 4.8): The Autoptimize WordPress plugin before 3.1.1 does not sanitise and escape some of its settings, which could allow high…
CVE-2021-24378 — Medium (CVSS 4.8): The Autoptimize WordPress plugin before 2.7.8 does not check for malicious files such as .html in the archive uploaded…
CVE-2021-24332 — Medium (CVSS 4.8): The Autoptimize WordPress plugin before 2.8.4 was missing proper escaping and sanitisation in some of its settings,…

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